Improved machine for making screws



A shaft c'.

i UNITED STATES PrvrENr OFFICE..

-JsTUs cruces, or UTIoA, Nnw YORK.

IMPROVED MACHINE FOR MAKING SCREWSJ Specification forming part ofLetters Patent No. 29,373, dated July 31,` 1860.

To all whom t may concern:

Be it known that I, JUsrUs GRIeGs, of Utica, in the State'of New York,have invented a new and useful Improvement in Machinery for Makingrood-Screws; and I do hereby declare that the following is afull, clear,and exact description thereof, reference being had to the accompanyingdrawings, making part of this specification, in which- Figure l is anend elevation; Fig. 2, a side elevation with the transferring-fingers ina horizontal position and with the feeding-tube and transferring-ungersin section. Fig. 3 is another elevation with the transferring-fingers ina vertical position, and Fig 4, a vertical section taken at the line A aof Fig. 3.

The same letters indicate like parts in all the figures.

My said invention relates to machinery for presenting and insertingscrew-blanks into the gripping-jaws, by which they are to be held androtated during the operation of suitable machinery, whether for shavingnicking, or reshaving the heads; but in the accompanying drawings it isrepresented as applied to machinery for shaving the heads.

In the accompanying drawings, a represents the usual mandrel andgripping-jaws of a machine for shaving the heads of screwblanks. Thejaws b are mounted in the head of the mandrel in the usual manner, andare operated to grip and liberate the screw-blank in the usual mannerbyarod inside the mandrel, to which they are linked, the rear end of thesaid rod being connected with a collar c on the mandrel, which is madeto slide back and forth by a cam CZ on the cam-shaft e. It is not deemednecessary to give a minute description and representation of thismechanism, as it is well known to persons versed in this branch of thearts. The screw-blanks from any suitable feeder are presented to anddescend point foremost in a vertical tube f,

and from this tube they enter one by one between'a pair ofspring-fingers f f', attached to and carried by an arm h on a rocking- Aspring j is interposed between the arms of the fingers, which by itstension tends constantly to close the fingers to make them grip theshank of the screw-blank gently; but

as they are thrown up in a horizontal position,

as in Fig. 2, they are forced open by a wedge lo on the lower end of thetubef. While the fingers are so open the shank of the screwblank fromthe tube enters between them and is stopped by the head. The fingers arethen vibrated from a horizontal to a vertical position by the rockingmotion of the arm h onthe rock-shaft t', to be presently described, andas the fingers leave the wedge lo they are closed by the tension of thespring j with sufticient force to hold the screw-blank during theoperation of transferring and inserting the end of the shank into thegripping-jaws on the mandrel a.

On the face of the arm h and between the levers of the fingers there isa head-gage plate l, adapted to slide thereon and over the grippingportion of the fingers, as represented. By means of a spring m thisplate is drawn toward the rocking-shaft c' to uncover the grippingportion of the fingers which receive the screw-blank; but as the fingersare vibrated from the horizontal to the vertical position the gage-plateZ is forced down over the head of the blank, and this is effected by itsupper end coming in contact with the curved face of a stationary cam n,placed above the rock-shaft. Now, as this operation is completed beforethe shank of the screw-blank is gripped by the jaws on the mandrel, anyresistance which the blank may receive as it is being inserted, whetherby the partial gripping of the jaws on the mandrel or by its pointcoming in Contact with a spring-stop in the mandrel or from any othercause, the inner face of the plate l forms a gage beyond which the headof the blank cannot be forced back, and as the arm h is rocked by apositive motion the series of blanks will all be inserted into andgripped by the jaws on the mandrel at the same distance from the outerface of the head. In this way whatever operation is to be performed onthe heads of the screwblanks the tool or tools employed for the purposewill always find the head of the screwblank in the required position,however the Shanks may vary in length. The rock-shaft z' carries a cranko at one end, which is connected by a jointed rod p with a lever o",that receives a vibratory movement from a filletcam s ou the cam-shaft,and in this Way the required rocking motion is imparted to the shaft t'to vibrate the arm h with the transferring-fingers from a horizontal toa vertical position and back again.

The tool for shaving the head is represented at t in a tool-post u,attached to a rock-shaft o, which is vibrated by a cam-groove in theface of a cam-wheelyon the carnshaft,which said cam-groove acts on anarm ,e on the rockshaft to move the cutter in and out.

Although I have described the gage-plate as sliding in the direction ofthe radius of the arm h, and have specified its movements as beingimparted in one direction by a xed cam and in the opposite direction bya spring, I do not Wish to be understood as limiting my claim ofinvention to such mode of application, as these may be greatly variedWithout changing the principle or character of my said invention-as, forinstance, it may be made to slide on and oft laterally, or it may behung on a fulcrurn-pin and vibrated thereon, and the motions may beimparted by amechanism operating positively in both directions; or,

described, for gaging the screw-blanks by the head when the blanks areinserted yin the grip-y ping-jaws, as set forth.

JUSTUS GRIGGS.

Witnesses: t

H. A. HARVEY, D. GILLMORE.

These several modes in which I have

